From Nick Greene,
Your Guide to Space / Astronomy.
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It was three days into the mission of Apollo 13; the date was April 13th, when the mission changed from a routine flight into a race for survival.

The technicians in Houston had also noticed unusual readings on their instruments and were starting to talk amongst themselves and to the crew of Apollo 13. Suddenly, Jim Lovell’s calm voice broke though the hubbub. "Ahh, Houston, we've had a problem. We've had a main B bus undervolt."

Immediately after attempting to follow Houston Flight Control’s last order to stir the cryo tanks, Astronaut Jack Swigert heard a loud bang and felt a shudder throughout the ship. Command module pilot, Fred Haize, who was still down in Aquarius after the television broadcast, and mission commander, Jim Lovell, who was in between, gathering cables up, both heard the sound, but at first thought it was a standard joke previously played by Fred Haize. It was no joke.

Seeing the expression on Jack Swigert’s face, Jim Lovell knew immediately that there was a real problem and hurried into the CSM to join his Lunar module pilot. Things did not look good. Alarms were going off as voltage levels of the main power supplies were dropping rapidly. If power was completely lost, the ship had a battery backup, which would last for about ten hours. Apollo 13, unfortunately, was 87 hours from home.

Looking out a port, the astronauts saw something, which gave them another concern. "You know, that's, that's a significant G&C. It looks to me looking out the ahh, hatch that we are venting something." A pause… "We are, we are venting something out the, into the ahh, into space."

A momentary hush fell over the Flight Control Center in Houston as the new information sank in. Then, a flurry of activity began, as the technicians all conferred, and other experts were called in. Everyone knew that time was critical.

As several suggestions for correcting the dropping voltage were raised and tried unsuccessfully, it quickly became apparent that the electrical system could not be saved.

Commander Jim Lovell’s concern was continuing to rise. “It went from `I wonder what this is gonna to do to the landing.' to `I wonder if we can get back home again.'" The technicians in Houston were having the same concerns.

The call was made that the only chance they had of saving the crew of Apollo 13 was to shut down the CM entirely to save their batteries for reentry. This would require the use of Aquarius, the lunar module as a lifeboat. A module equipped for two men for two days would have to sustain three men for four.

The men quickly powered down all the systems inside Odyssey and scrambled down the tunnel and into Aquarius. The crew of Apollo 13; Jim Lovell, Fred Haize, and Jack Swigert all hoped it would be their lifeboat and not their tomb.

• Next page > Part 3: A Cold and Frightening Journey > Page 1, 2, 3, 4

Full Size Images

• Apollo 13 Mission Patch
• View Of Damaged Apollo 13 Service Module
• View Of Earth As Seen From Apollo 13
• Apollo 13 Crew

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